California’s state building-machinery operators have rejected a contract offer from Gov. Jerry Brown and authorized a strike against the state, according to the union’s top representative.

The government’s offer was “soundly rejected,” said Steve Crouch, who represents about 850 members of the International Operating Engineers Union Local 39 (Bargaining Unit 13). He would not disclose how many members voted or the percentage of ballots that turned down the tentative agreement. “No” votes were also counted as support for authorizing a strike.

The operating engineers, who manage vast heating, cooling, water and other systems for prisons, office buildings and other state facilities, had sought more than the phased-in 4.5-percent across-the-board pay raise that Brown offered, arguing that their salaries are well below those of counterparts in other government agencies and the private sector.

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The strike authorization vote doesn’t mean that workers will walk out, but it gives the union’s board authority to call a strike. Many public-employee contracts contain a no-strike provision in return for terms that keep expired contracts in effect until a new deal is in place and forbid employee lockouts. Workers who violate those provisions face could be disciplined or even fired.

That threat didn’t keep American Federation of State, County and Municipal Employees from striking against the University of California hospital system three times over the course of a year when its contract negotiations bogged down.

That union, whose members are under the authority of the UC Board of Regents, planned a fourth strike earlier this year but called it off after reaching an agreement.

No state employee union under gubernatorial authority has ever gone out on strike, but earlier this year Crouch said his members are prepared to “engage in an AFSCME-type action” if talks stalled. He noted that other operating engineers locals have staged actions against cities and businesses: “Strikes are not uncommon in our union.”

With talks for a bigger salary increase stalled, the operating engineers’ board sent Brown’s offer to members last month. Their rejection comes as another union, the California Association of Professional Scientists, is preparing to send a similar agreement to its members for a vote that will be tallied June 30.

Like the operating engineers, the scientists wanted more than the 4.5 percent raise Brown offered. The board sent the deal to members without a recommendation to vote for it.

A third union that represents state attorneys, hearing officers and adjudicating law judges is also without a labor agreement. Its negotiators are still in talks with the Brown administration.

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